<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
</head>
<body>

</body>
<script type="text/javascript">
	function a(){
	  	 suiji = parseInt(Math.random()*100);
	  	if(suiji%7==0){
	  		return suiji;
	  		
	  	}else{
			a()
		}
	}
	a()
	console.log(suiji)
	</script>
</html>